Gyratory crushers



Jan. 21, 1969 DURAND I 3,423,033

GYRATORY CRUSHERS Filed July 5. 1966 Sheet of 4 Jan. 21, 1969 P. DURAND GYRATORY CRUSHERS Sheet Filed July 5. 1966 .0 T T. TT I Lil lLLi TfiTTi T Jan. 21, 1969 P. DURAND GYRATORY CRUSHERS Sheet Filed July 5, 1966 v i 10! H 6 V Z L I FiG.7

Jan. 21, 1969 P. DURAND 3,423,033

GYRATORY CRUSHERS Filed July 5, 1966 Sheet i of 4 Ficsm ""Ficss FiG.|0

United States Patent 3,423,033 GYRATORY CRUSHERS Pierre Durand, Lyon, Rhone, France, assignor to Richier,

Paris, France, a company of France Filed July 5, 1966, Ser. No. 562,761

Claims priority, application France, July 8, 1965, 46,200; Jan. 21, 1966, 46,844

US. Cl. 241-32 8 Claims Int. Cl. B02c 17/08, 19/00 ABSTRACT OF THE DISCLOSURE A gyratory crusher in which an eccentric carries and actuates the shaft of a crushing head which is journalled in a body which is in turn freely mounted inside the frame of the crusher and rests on a hydraulic jack. The body is subjected to a torque tending to make it revolve in a direction opposite that of the crushing head but is connected to the frame of the crusher by an arrangement including a retaining device associated with the hydraulic jack so that if the torque required for the crushing operation exceeds a predetermined value, the reverse torque on the body carrying the movable members of the crusher drives the body in the opposite direction and acts through its retaining device on the jack to reduce the gripping action of the crusher until the torque is normal again, whereupon the initial gripping action of the crusher is restored.

Gyratory crushers are usually provided with means preventing them from being damaged, which means make it possible for the crushing head and the bowl to be momentarily spaced with respect to each other in the event an uncrushable object enters the gap between said two members.

One of such known means consists in mounting the movable members of the crusher on a central hydraulic jack of which the vertical thrust on said members is automatically released at the right moment.

The subject-matter of the present invention is a gyratory crusher of the above-mentioned kind, in which the eccentric carrying and actuating the shaft of the crushing head is journaled in a body which is in turn freely mounted inside the frame of the crusher and rests upon a hydraulic jack; said body is subjected to a torque tending to make it rotate in the opposite direction to the crushing head but is connected to the frame through an arrangement including a retaining device associated with the above-mentioned hydraulic jack, so that, if the torque required for the crushing operation exceeds a determined value, the reverse torque on the body carrying the movable members drives said body in the opposite direction and thus acts automatically, through its retaining device, on the jack to reduce the gripping action of the crusher till the torque is normal again, at which time the normal grip of the crusher is restored.

Said retaining device advantageously comprises a cylinder linked to the frame of the crusher and closed by a cover through which a rod passes, said rod being linked to the body carrying the movable members and ending in a plunger on which one end of a helical spring takes its movable bearing while the other end of said spring takes its fixed bearing on said cover, the chamber between said plunger and the bottom of said cylinder being connected with the cylinder of the hydraulic jack.

According to a modified embodiment of the present invention, the momentary spacing of the crushing head and the bowl is obtained by means of a hydraulic slide valve fed at the same time as the jack setting the position of the crushing head inside the bowl; the slide of said valve, the position of which depends on the value of the reaction torque acting through a roller keyed on said slide and acted upon by an inclined member integral with the mechanism body, is provided with tapered slits which let a leakage flow pass, which fiow depends on the resistance torque and acts upon the feed to the above-mentioned jack setting the position of the crushing head inside the bowl, while a helical spring bearing on the body of the crusher counterbalances, under normal operating conditions, the reaction of the crushing torque.

The invention will be further described hereinafter, with reference to the appended diagrammatic drawing which illustrates, by way of nonlimiting examples, two embodiments of the gyratory crusher of the invention.

In said drawing:

FIGURE 1 is a cross-sectional view of a first embodiment of the crusher of the invention;

FIGURE 2 is a partial view thereof in plan and in horizontal section;

FIGURES 3, 4 and 5 are, on an enlarged scale, longitudinal sectional views of the retaining device, in its working position and in two positions corresponding to two possible operations thereof respectively;

FIGURE 6 is a vertical sectional view of the second embodiment of the gyratory crusher of the invention;

FIGURE 7 is a sectional view of same along line 77 of FIGURE 6;

FIGURE 8 is a partial sectional view, on an enlarged scale, along line 8-8 of FIGURE 6;

FIGURES 9, 10 and 11 are views of the hydraulic slide valve on an enlarged scale, in sections along lines 99, 1010, 11-11 of FIGURE 8 respectively.

In FIGURE 1, 2 indicates the frame of the crusher, 3 is the bowl surrounding the latter, 4 is the crushing head movable inside said bowl and carried by a spindle 5 mounted in an eccentric 6 the bottom of which carries a toothed crown 7. By means of bearings '8 and 9 the eccentric 6 is mounted to rotate freely inside a body 10 capable of rotation and translation inside the bores 12 and 13 in the frame 2. Said body 10 rests on the plunger 14 of a hydraulic jack the cylinder 15 of which is connected through a line 16 to a source of fluid such as a pump or an accumulator.

f he body 10 resting on the jack 14-15 carries the driving motor 17 for the crusher, the shaft of said motor carrying a bevel pinion '18 meshing with the crown 7.

A cylinder 22 closed by a screwed cover 23 is linked at 21 to an arm 19 on the frame 2. The rod 24 of a plunger 25 passes through the cover 23. Said rod 24 is linked at 26 to an arm 27 integral with the body 10 resting on the jack 14-15. A helical spring 28 is housed inside the cylinder 22 between the plunger 25 and the cover 23, said spring 28 tending to maintain the plunger 25 at the bottom of the cylinder 22. The chamber 29 which is nevertheless defined by the plunger 25, the bottom of the cylinder 22 and the side wall of said cylinder, is connected through a line 30 to the cylinder 15 of the jack 14-15.

The operation of the crusher just described is as follows:

After the distance 31 between the bowl 3 and the crushing head 4 has been set according to the crushing fineness desired, this being achieved by feeding an ade quate quantity of fiuid into the jack 141'5, the rotation of the motor 17 causes, in a way known per se, the material fed to be crushed. With the eccentric 6 rotating in the direction of the arrow 32 of FIGURE 2, the body 10 tends, through reaction, to rotate in the direction of the arrow 33 of same figure. This rotary action of the body 10 is however restrained by the cylinder 22 ensuring the connection of said body 10 to the frame 2.

When the crusher is operating normally, the torque exerted in the direction of arrow 33 subjects the abovementioned cylinder 22 to an extension stress in the direction of the arrow 34 of FIGURE 3. Additionally, the pressure of the oil on the plunger 25 in the chamber 29 of the cylinder 22 is added to said stress. These two stresses have however a lower value than the initial tension of the spring 28 so that, under normal operating conditions, the distance between pivots 21 and 26 remains unchanged.

If, on the contrary, the torque indicated by the arrow 33 exceeds a predetermined value as a result of the feeding of harder material to the bowl 3, the spring 28 begins to be compressed, which results in increase of the volume of the chamber '29 as shown in FIGURE 4. A certain quantity of the oil in the jack 14l5 is thus admitted into the chamber 29. The body '10 and all the crusher members carried by the jack 14-15 are thus lowered, with the result that the space 31 between the bowl 3 and the crushing head 4 is increased, so that the material can pass therethrough. Then, when the crushing strength is back to its normal value, the torque comes back to its equilibrium value and the spring 28 goes back to its position shown in FIGURE 1, thus causing the movable members of the cr'usher to return to their normal operating positions.

It should be noted that if, a hard object such as, for instance, a metal part falls into the crusher, the crushing strength suddenly reaches a very high value, and the spring 28 is then compressed to such an extent that, as shown in FIGURE 5, the plunger 25 exposes an annular groove 35 which, through a port 36, is connected with an oil tank 37, with the result that the oil is very quickly expelled outside its normal path so that the movable members of the crusher are lowered very quickly, it being impossible for them, however, to return automatically to their normal positions. On the other hand, it is advantageous to associate with the rod 24 an arm 38 which, when the plunger 25 exposes the groove 35, actuates a switch 39 opening the control circuit for the motor 17, so that the operation of the crusher is automatically stopped. To restore the normal operating conditions it is necessary to remove the foreign body lying between the bowl 3 and the crushing head 4 and to fill the jack 14-15 with oil again.

FIGURES 6 to 11 illustrate another embodiment of a gyratory crusher according to the invention. In these figures, 40 indicates the frame of the crusher, 42 is the bowl which surmounts said frame and 43 is the crushing head carried by a shaft 44.

The shaft 44 is mounted to revolve freely in two ball bearings 45 and 46 fixed out of center in a hollow shaft 47 two ends of which are guided by bearings 48 and 49 fixed in the casing 50 of the mechanism, as shown in FIG- URE 6.

The electric motor 52 drives the hollow shaft 47 through gears 53 and 54 and is fixed on said casing or barrel 50-.

The lower part of the casing 50 forms a plunger 55 which is housed inside a cylinder 56 inserted in the frame 40 and bears on the oil which fills said cylinder, so that the elevation of the casing 50 and the crushing head 43 varies in accordance with the quantity of oil fed to the chamber of the jack thus formed.

The casing 50, being positioned at its lower end by the cylinder '56 and at its upper end by a cylindrical fitting member 57 in the frame 40, is free to revolve around a vertical axis.

A stop 58 provided on the flared tube 59 built on the barrel 50 and supporting the motor 52, as shown in FIG- URE 7, bears on a spring 62 through a shouldered rod 60, the other end of said spring 62 abutting against the bottom of a cap 63 secured to the frame 40.

Said spring 62 absorbs the reactions resulting from the crushing torque: the greater the crushing strength the greater the angular shifting of the flared tube 59 and the more the spring 62 is compressed.

The lower part of the frame 40 is arranged so as to constitute a tank 64 which is filled with oil and contains a hydraulic pump 65- driven by an auxiliary motor 66, and a valve 67 fed at the same time as the cylinder 56.

As shown more fully in FIGURES 9, 10 and 11, said valve 67 includes a body 68 in the lower part of which two grooves 69 and 70 are machined.

The groove 6-9 is connected with the pump 65 while the groove 70, termed an escape groove, is connected through a line 72 to a basin 73 provided in the body 50 so as to ensure the feed of the lubricating circuit for the mechanism of the crusher.

A slide valve 7-4 movable inside the bore 75 of the body 68 ensures and controls the supply of oil between the two grooves and is provided with tapered slits 76.

A spring 77, one end of which bears on a cap 78 inserted on the body 68 while its other end bears on the slide valve, urges the latter to its lowermost position.

The slide valve 74 is extended outside the body 68 by means of a threaded stem 79 on which a support '80 is screwed, a rod 82 screwed in the body 68 preventing the rotation of said support 80. The latter carries a pin on which a roller 83 is keyed.

A helical gear 84 keyed on a shaft 85 which passes slantwise through the body 68 and is provided with an operating handwheel 86 meshes with a spur gear 87 cut in the slide valve 74.

This arrangement makes it possible to adjust the lift of the valve according to the degree of granulometry desired.

An arm 88 integral with the body 50 includes a cam 89 comprising a straight section extended by an inclined plane, as shown in FIGURES 9 and 11. Said cam 89 is disposed so as to come into contact with the lower part of the roller 83.

The operation of the crusher according to the embodiment just described is as follows: initially the valve 74 is closed, there is no oil in the cylinder 56 and the body 50 of the crusher is in its lowermost position, with the plunger 55 resting on the bottom of the cylinder. The motor 66 is started, the oil immediately supplied by the pump 65 enters the cylinder '56 and causes the plunger and the crusher body to rise while carrying along the cam 89 the right hand side part of which comes into contact with the roller 83 and lifts it. As a result the slide valve 74 moves upwards and there takes place an oil leakage which, through the slits 76, the groove 70 and the line 72, feeds the basin 73. Equilibrium will be achieved when the leakage flow is equal to the flow of the pump, at which time the plunger 55 will stop moving upwards and the crushing head 43 will be set at a constant level which will define the degree of granulometry. If it is desired to modify the latter, the operator turns the handwheel 86 whereby the roller 83 is shifted as already explained hereinabove.

On starting the motor 52, the crushing head 43 starts revolving in the direction of the arrow 90' in FIGURE 7. the crushing of the material in the bowl 42 then develops a resistance torque which tends to make the body 50 revolve in the direction of the arrow 92 of said FIGURE 7. Under normal operating conditions, said torque is merely absorbed by the spring 62, the roller 83 of the valve 67 bearing on the right hand side part of the cam 89. The slide valve 74 is in the position shown in FIG- URE 10, which position corresponds to the degree of granulometry desired.

It the crushing torque increases beyond its normal value, the reaction torque increases to the same extent and makes the body 50 pivot slightly in the direction of the arrow 92 around the vertical axis of the crusher, whereby the spring 62 is compressed to a greater extent and the inclined section of the cam '89 takes up a posi' tion below the roller 83.

Thus the slide valve 74 is slightly moved upwards, which increases the leakage flow of the slits 76 beyond the flow of the pump, which causes as a consequence the lowering of the body 50 and the crushing head 43. As a result, the power absorbed and the reaction torque decrease and a new equilibrium tends to be created.

When a noncrushable hard body is fed to the bowl 42, the reaction torque immediately reaches a high value, the action of the inclined plane of the cam 89 becomes very important, and the slide valve 74 rises a great distance, connects the two grooves 459 and 70 and clears the lower opening of the bore 75.

Immediately, the entire flow of oil from the pump 65 and the amount of oil contained in the cylinder 56 pass through said opening and cause the quick lowering of the body 50 as well as the automatic cut-off of the supply of power to the main motor 52.

As a result of this arrangement, the decompression of the cylinder 56 is carried out very quickly, whereas it would not be soif the entire leakage flow should pass through the line 72 as is the case under normal operating conditions.

A ball valve 93 housed in the lower section of the slide valve 74 makes it possible, in the event of an accidental excess pressure in the circuit, for the oil to escape directly to the oil tank 64 through a line having a wide crosssection, so that the pump is protected. Such excess pressures may be caused by vertical overloads acting on the crushing head.

What I claim is:

1. A gyratory crusher of the type in which the movable members rest on a central hydraulic jack, characterized in that the eccentric carrying and actuating the shaft of the crushing head is journaled in a body which is in turn freely mounted inside the frame of the crusher and rests on a hydraulic jack, said body being subjected to a torque tending to make it revolve in the opposite direction to the crushing head but being connected to the frame of the crusher by an arrangement including a retaining device associated with said hydraulic jack, so that, if the torque required for the crushing operation exceeds a predetermined value, the reverse torque on the body carrying the movable members of the crusher drives said body in the opposite direction and acts thus automatically, through its retaining device, on the jack to reduce the gripping action of the crusher till, when the torque is normal again, the initial gripping action of the crusher is restored.

2. A gyratory crusher as claimed in claim 1, characterized in that the device for tangentially retaining the body supporting the movable members comprises a cylinder linked to the frame of the crusher and closed by a cover through which a rod passes, said rod being linked to the body supporting the movable members and ending in a plunger on which a helical spring takes its movable bearing while the other end of said spring takes its fixed bearing on said cover, the chamber between said plunger and the bottom of said cylinder being connected with the cylinder of the hydraulic jack.

3. A gyratory crusher as claimed in claim 1, characterized in that the momentary spacing of the crushing head and the bowl is obtained by means of a hydraulic valve fed at the same time as the jack setting the position of the crushing head inside the bowl, the slide of said valve, the position of which depends on the value of the reaction torque acting through a roller keyed on said slide and acted upon by an inclined member integral with the mechanism body, being provided with tapered slits which let pass a leakage flow depending on the value of the resistance torque, which flow acts upon the feed to said jack setting the position of the crushing head inside the bowl, while a helical spring bearing on the body of the crusher counterbalances, under normal operating conditions, the reaction of the crushing torque.

4. A gyratory crusher as claimed in claim 3, characterized in that the body of said slide is extended outside said valve by a threaded stern on which the support for the roller controlling the movements thereof is screwed, while a spring bearing on a cap inserted on the upper part of the valve and against the slide returns constantly the latter to its lower-most position so as to ensure the closing of the valve.

5. A gyratory crusher as claimed in claim 4, characterized in that an operating. handwheel keyed to a shaft passing slantwise through said valve is provided with a helical gear meshing with a spur gear cut in the periphery of the slide and allows manually adjusting the position of the latter inside the valve in accordance with the degree of granulometry desired, the support of the roller being prevented from rotating so as to act as a fixed nut.

6. A gyratory crusher according to claim 5, characterized in that the cam secured to the freely revolving mechanism body is advantageously made of two sections, one straight and the other inclined, the latter acting on the roller integral with the slide only when the reaction of the torque reaches too high a value.

7. A gyratory crusher as claimed in claim 6, characterized in that the escape groove of the valve, directly connected to the lubrication circuit of the apparatus, is disposed very close to the lower end of said valve immersed in the oil tank of the apparatus, and below the groove connected with the feed circuit, so that, when a substantial overload occurs, said slide connects up said groove directly with said tank in order to cause the quick discharge of the jack carrying the crushing head.

8. A gyratory crusher as claimed in claim 7, characterized in that a ball valve housed in the lower section of the slide ensures simultaneously the protection of the pump against an undue overpressure, and the lowering of the crushing head when the latter is subjected to too great vertical stresses.

References Cited UNITED STATES PATENTS 2,579,5 16 12/1951 Roubal 241-215 2,267,984 6/1954 Gruender 24l215 2,680,571 6/1954 Bjarme 241215 X 3,133,706 5/1964 Mertz 241-32 DONALD R. SCHRA N, Primary Examiner.

F. T. YOST, Assistant Examiner.

US. Cl. X.R. 

